The second week of March 2017 was a momentous week for the global standardization of 5G, known as 5G New Radio or 5G NR. The big news was that 3GPP agreed on an accelerated 5G schedule that will enable 3GPP-based large-scale trials and deployments as early as 2019. This development is truly exciting and shows that the industry has come together and is working collaboratively toward the common goal of enabling early enhanced 5G mobile broadband deployments, while still ensuring forward compatibility, to enable the broader 5G vision.
But there were many other important outcomes of the 3GPP meeting, including one in particular that I want to expand on: the new study on 5G NR operating in unlicensed spectrum, both licensed-assisted and stand-alone. A study item is the first step in the 3GPP process of standardizing key technologies, and what makes this study item noteworthy is that this is the first time 3GPP will be studying the development of a cellular technology operating solely in unlicensed spectrum. It is also significant that the 3GPP-approved study includes a wide array of unlicensed spectrum ranges, all the way to 60 GHz also known as mmWave. The study will be led by Qualcomm together with other partners and will run through the beginning of 2018.
You may ask why this is such a big deal. It’s because 5G NR will proliferate around the world more broadly and more rapidly if all spectrum types can be used, especially unlicensed spectrum. Doing so will allow 5G to support more uses and deployments models so that many more entities will be able to enjoy the benefits of 5G in a much broader 5G ecosystem. Using unlicensed spectrum on a stand-alone basis enables a wider variety of new deployment scenarios, such as local area networks in dense deployments, so-called private IoT networks for enterprises or Industrial IoT (explicitly called out in the project descriptions in 3GPP), neighborhood networks, and neutral host deployments (where one deployment serves multiple operators). Examples where such private IoT networks can be deployed are anything from factories, ports, and mines to warehouses and smart buildings. Enabling the use of unlicensed spectrum assisted by licensed spectrum, will allow mobile operators to aggregate more spectrum to provide extreme bandwidths and more capacity (Figure 1). In other words, consumers will enjoy faster, better broadband if 5G uses unlicensed spectrum.
The expansion of cellular technologies into unlicensed spectrum did not happen overnight. As with many ground-breaking concepts, the development of these new technologies has been a process with a great deal of hard work and many innovations along the way. I remember discussing the idea of bringing cellular LTE technology to unlicensed spectrum in our labs more than four years ago, which then evolved to the concept that we presented at our yearly financial event in November 2013 and at the 3GPP Plenary of December 2013.
A good idea for a new technology often branches into many concepts and the first member of this technology family is referred to as LTE-U. LTE-U is focused on enabling faster downloads for consumers by aggregating LTE in unlicensed spectrum with an ‘anchor’ channel in licensed spectrum. It was a revolutionary concept at the time and we had to work diligently to make it reality, especially by demonstrating that LTE was sharing the unlicensed spectrum fairly with Wi-Fi. Our efforts are now bearing fruit. Last month, the U.S. Federal Communications Commission (FCC) announced that it issued the first approvals for LTE-U equipment and on the same day T-Mobile U.S. announced that they are deploying LTE-U and plan to introduce it to consumers this spring.
The next member of this technology family is called Licensed Assisted Access or LAA. It also uses an anchor channel in licensed spectrum, but it added new functionality to LTE to enable a fully global deployment, such as “listen before talk”. LAA was first studied in 3GPP in 2014 and the standard was finalized in early 2016. Using LAA, a far greater number of operators around the world will be able to offer gigabit LTE speeds to consumers as exemplified recently by Vodafone’s LAA-ready commercial network in Turkey.
The final member of this family of technologies is MulteFire, and it may be the most far reaching. Unlike LTE-U and LAA, MulteFire allows entities without any access to licensed spectrum to provide the benefits of LTE technology and ecosystem. This is accomplished by enabling LTE to operate in unlicensed spectrum on a standalone basis—in other words, without any anchor channel in licensed spectrum. We announced the concept in June 2015 and earlier this year the MulteFire Alliance finalized the MulteFire 1.0 specification.
Another milestone was met at the recent Mobile World Congress in Barcelona last month, where we demonstrated seamless mobility in an over-the-air MulteFire network with multiple small-cells. Remember that MulteFire is operating in 5 GHz unlicensed spectrum that is shared with Wi-Fi, so the MulteFire device in our mobile van driving around our San Diego campus was fairly coordinating with many other active, independent, commercial Wi-Fi access points. Seamless mobility in unlicensed spectrum is truly a groundbreaking accomplishment that shows the potential of expanding cellular technologies to new use cases and new spectrum types.
So let’s go back to the ground breaking week in March, when 3GPP approved a study of 5G NR in unlicensed spectrum, both with an ‘anchor’ in licensed spectrum (the 5G LAA version) and stand-alone in unlicensed spectrum (the 5G MulteFire version). In other words, NR in unlicensed will become the 5G evolution path for both LAA and MulteFire. This study will eventually result in expanded functionalities for 5G in future 3GPP releases that are part of our 5G NR Spectrum Sharing vision, or NR-SS for short. We still have more work to do, but we are working meticulously to ensure that 5G NR will support all spectrum types, including new exciting spectrum sharing paradigms enabled by NR-SS, so that a wider ecosystem can enjoy the benefits of 5G.